Which of the following has zero valency?

Which of the following compounds has a square pyramidal structure?

Which inert gas has the highest boiling point?

Which of the following is the life-saving mixture for an asthma patient?

The chemical structures of $XeO_3$ and $XeOF_4$,respectively,are

Assertion $(A)$: The boiling points of noble gases increase from $He$ to $Xe$.
Reason $(R)$: The interatomic van der Waals' attractive forces increase from $He$ to $Xe$.
The correct answer is: